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Automatic Dynamic Run-time Optical Network Reservations. John R. Lange Ananth I. Sundararaj and Peter A. Dinda Prescience Lab Department of Computer Science Northwestern University http://plab.cs.northwestern.edu. Introduction.
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Automatic Dynamic Run-time Optical Network Reservations John R. Lange Ananth I. Sundararaj and Peter A. Dinda Prescience Lab Department of Computer Science Northwestern University http://plab.cs.northwestern.edu
Introduction • Recently the Grid community has begun turning the network into a standard grid service • Network and compute resources are still very different • Requires in depth understanding of program behavior or targeted application development • VRESERVE • Enable unmodified applications to efficiently utilize reservation based networks without user intervention
Overview • Reservations and Circuit Switching • Optical Networking • OMNInet and ODIN • Virtual Machines • Virtuoso • Overlay Networking • VNET and VTTIF • Putting it all together • VRESERVE • Performance Evaluation
Reservable Networks • Generic Reservation API • CreatePath(<srcIP>, <dstIP>, <bw>, <lat>); • TeardownPath(<srcIP>, <dstIP>); • Somebody or something has to make the API calls • Circuit switching and network reservations are inherently linked • Establishing a circuit is similar to reserving the network elements along a path
Reservation Issues • Parameter Values • How does someone determine the required bandwidth and latency? • Are the endpoints always evident? • Highly parallel applications in a grid environment • Migratable Virtual Machines • Time • What is the flow duration? • What is the traffic behavior pattern? • Applications often have cyclical behaviors (compute and send)
Reservation Problems • Complexity: • Someone has to call the reservation API • Developer must incorporate API calls into application • User must reserve network on application’s behalf • Efficiency: • Efficient reservations require understanding application’s behavior and topology • Networks usually reserved in spatial and temporal blocks • Networks reserved to connect all hosts • Networks reserved for entire execution time
Optical Networks • Recent advances in switching technology have brought renewed interest to the area • Offer provisioning of dynamic lightpaths • One of the latest incarnations of circuit switched networking • Emergence of network reservation grid services • Generating a large deal of interest in the high performance computing and grid communities • NLR, Canarie, Netherlight • OptIPuter
OMNInet and ODIN • OMNInet • Experimental dynamically configurable optical network • Provisionable wavelengths (lambdas) • All-to-All topology • Connects research centers in Chicago and Northern Illinois • ODIN • Reservation system for OMNInet • Developed by iCAIR • International Center for Advanced Internet Research • Mambretti, J., Weinberger, J., Chen, J., Bacon, E., Yeh, F., Lillethun, D., Grossman, B., Gu, Y., and Mazzuco, M. The photonic terastream: Enabling next generation applications through intelligent optical networking at iGRID2002.
ODIN • Lightpath Reservation System • Implements path discovery based on user supplied endpoints • Also beginning to look at scheduling services • Command line client interfacing with a trusted server • Interface • oclient -c <srcIP> <dstIP> <lambda#> <flags> • Path Creation • oclient -t <pathID> • Path Teardown
Optera 5200 OFA 5200 OFA l 1 l 2 l 3 Optera 5200 10Gb/s TSPR Optera 5200 10Gb/s TSPR l 4 5200 OFA 5200 OFA Fiber W Taylor Host 10 GE l Photonic 1 PP VM 10 GE l Node 2 8600 1 Gbps l Optera 5200 10Gb/s TSPR 3 l 4 NWUEN-2 NWUEN-3 Lake Shore Internet 10 GE l PP 1 Photonic 10 GE l 8600 2 Node l 3 l 4 Internet NWUEN-8 NWUEN-9 NWUEN-4 S. Federal Network Path Taken 10 GE 1 Gbps Host PP Photonic 10 GE 8600 Node VM Potential Paths http://www.dotresearch.org
VirtuosoVirtual Machine marketplace • Collection of remotely distributed VMs that appear to reside on the same LAN • Provides many opportunities for optimization • Adaptive overlay networks, VM migration, resource scheduling, etc… • A. Sundararaj, A. Gupta, and P. Dinda, Increasing Application Performance In Virtual Environments Through Run-time Inference and Adaptation • HPDC 2005 • A. Sundararaj, M. Sanghi, J. Lange, P. Dinda, An Optimization Problem in Adaptive Virtual Environments • (MAMA 2005), To Appear • http://virtuoso.cs.northwestern.edu
Data Control
VNETVirtual Networking for Virtual Machines • Allows VMs to behave as if they were on the same LAN • All remote VMs tunnel traffic to a central proxy • Default star topology • A. Sundararaj, P. Dinda, Towards Virtual Networks for Virtual Machine Grid Computing • USENIX VM 2004
Data Control
VTTIFApplication Topology Inference • Extracts network topologies from application behavior • Generates a global traffic matrix defining the global application network topology • A. Gupta, P. Dinda, Inferring the Topology and Traffic Load of Parallel Programs Running In a Virtual Machine Environment • Workshop on Job Scheduling Policies for Parallel Processing, 2004
VADAPTOverlay Network Adaptation • Modify virtual network to match actual network topology • Creates overlay links between communicating VMs • Based on global reduction of VTTIF matrices • A. Sundararaj, A. Gupta, P. Dinda, Dynamic Topology Adaptation In Virtual Networks of Virtual Machines • LCR 2004 • A. Sundararaj, A. Gupta, and P. Dinda, Increasing Application Performance In Virtual Environments Through Run-time Inference and Adaptation • HPDC 2005
Data Control
VRESERVENetwork Reservations for Overlay Networks • Extension to VADAPT • Allows true adaptation of the network • Components • Reservation API interface • ODIN CLI • Routing mechanism • Address mapping service • Path Discovery • Depends on Reservation System functionality • Allows for scheduled and delayed reservations • Greatly increases usability for scheduler based reservation systems
Optical Overlays • VRESERVE routing is accomplished with VNET overlay links • Issues • Reservation based resources usually aimed at high performance • Application unaware of changing network conditions • TCP performance is typically poor in high performance networks • Benefits • Application unaware of changing network conditions • Routing is much easier at the overlay level • Network is capable of reacting to global state changes
Optera 5200 OFA 5200 OFA l 1 l 2 l 3 Optera 5200 10Gb/s TSPR Optera 5200 10Gb/s TSPR l 4 5200 OFA 5200 OFA Fiber (MWUEN-4) length = 5 miles W Taylor Host 10 GE l Photonic 1 PP VM 10 GE l Node 2 8600 1 Gbps l Optera 5200 10Gb/s TSPR 3 l 4 VNET NWUEN-2 NWUEN-3 VTTIF + VADAPT Lake Shore 10 GE l PP 1 Photonic 10 GE l 8600 2 Node l 3 l 4 VRESERVE ODIN Internet NWUEN-8 NWUEN-9 NWUEN-4 S. Federal Internet 10 GE 1 Gbps Host PP Photonic 10 GE 8600 Node VM http://www.dotresearch.org
Evaluation • This is an existence proof • Possible to automatically reserve network resources on unmodified application’s behalf • Caveats and Disclaimers • Scalability is unknown • Final performance measurements are also unknown • Infrastructure issues prevented complete performance evaluations • Only one functional optical link • Network dismantled during experiments
Performance Improvement(Synthetic BSP benchmark) Demonstrable improvement by using automatic reservations
Making VNET faster • Overlay links switched to UDP • Reliable transport implemented in VM TCP stack • 2x improvement • Lookup table caching • 3x improvement • Future: • Memory mappings for packet operations • In kernel forwarding • Specialized VM device drivers
VNET Performance (Round 2) • No results on Optical Network • Infrastructure unavailable • Experiments conducted between cluster nodes w/ gigabit Ethernet • VNET performance only • Reservation and adaptation systems unused • Overheads insignificant
Future Work • Where does this fit into the overall optimization problem? • How do we define the overall optimization problem? • Extension to other reservation systems, e.g. GARA
Conclusion • Networks are not generic grid services • Middleware is required to make reservation networks usable • VRESERVE • Enable unmodified applications to effectively utilize reservation based networks without user intervention
Prescience Lab • http://plab.cs.northwestern.edu • Virtuoso • http://virtuoso.cs.northwestern.edu • DOT (Distributed Optical Testbed) • http://www.dotresearch.org
Optical Network Performance Throughput